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TALK Abstracts Fermi and Jansky 2011 TALK Abstracts F-GAMMA program - review and recent findings: Unification and physical interpretation of the radio spectra variability patterns in Fermi blazars and jet emission from NLSy1s Emmanouil Angelakis L. Fuhrmann, I. Nestoras, R. Schmidt, C. M. Fromm, J. A. Zensus, N. Marchili, T. P. Krichbaum (Max-Planck-Institut fur Radioastronomie), H. Ungerechts, A. Sievers, D. Riquelme (Instituto de Radio Astronoma Milimtrica (IRAM)), M. Perucho-Pla (Departament dAstronomia i Astrofsica. Universitat de Valencia) F-GAMMA program - review and recent findings: Unification and physical interpretation of the radio spectra variability patterns in Fermi blazars and jet emission from NLSy1s The F-GAMMA program aims at understanding the physics at work in AGNs via a multi-frequency monitoring approach. A number of roughly 65 Fermi-GST detectable blazars are being monitored monthly since January 2007 at radio wavelengths. The core program relies on the 100-m Effelsberg telescope operating at 8 frequencies between 2.6 and 43 GHz, the 30-m IRAM telescope observing at 86, 145 and 240 GHz and the APEX 12-m telescope at 345 GHz. For the targeted sources the LAT instrument onboard Fermi-GST provides gamma-ray light curves sampled daily. Recently the program has further expanded with the participation of the Korean VLBI network, the Abastumani optical observatory and the Skinakas observatory for optical polarimetry. Here we will discuss: A. A review of all participating facilities and the main characteristics of the program (sources sample, frequency coverage, sampling etc.). The recent developments in optical coverage (in total power and polarization) will also be discussed. B. We show that, on the basis of their variability pattern, the observed quasi-simultaneous broad- band spectra can be classified to merely 5 classes. The variability for the first 4 is clearly dominated by spectral-evolution while sources of the last class vary self-similarly with almost no apparent shift of the peak frequency. It is shown that the former classes can be attributed to exactly the same two-component system made of (a) a quiescent optically thin spectrum and (b) a superposed flaring event; whereas the latter class must be interpreted in terms of a completely different mechanism. The apparent differences among the classes are explained in terms of a redshift modulus and an intrinsic- source/flare parameters modulus. Numerical simulations we have conducted show that a shock-in-jet model can very well describe the observed behavior. On the other hand, it is shown that the ability of the shock-in-jet to reproduce the behavior of sources that cover a broad spectrum of intrinsic properties indicates its universality. It is concluded that only two mechanisms seem to be producing variability. None of the almost 90 sources used for this study show a switch of class indicating that the variability mechanism is either (a) a finger-print of the source, or (b) that the parameters it may depend on vary at timescales far longer than the monitoring period of almost 4 years. C. Finally, we discuss recent findings of the program such as red-shift bias free correlation between radio and gamma-ray flux density. Furthermore, recently it has been found that besides the blazars and the radio galaxies, that have traditionally been thought to be the gamma-ray emitting AGNs, Narrow Line Seyfert 1 galaxies also show gamma-ray emission. Within the F-GAMMA program radio jet emission has been detected from 3 such sources challenging the belief that jets are associated with elliptical galaxies. The results of their monitoring will be discussed. 1 The gamma-ray blazar B0208-512, a multi-wavelength investigation Jay Blanchard (School of Mathematics & Physics, University of Tasmania, Australia), Jim Lovell (School of Mathematics & Physics, University of Tasmania, Australia), Roopesh Ojha (NASA Goddard Space Flight Center, USA), Matthias Kadler (University of Wurzburg, Germany), Roberto Nesci (University La Sapienza, Italy), Philip Edwards (CSIRO Astronomy and Space Science, ATNF, Australia), Michael Dutka (Catholic University, USA), Tapio Pursimo (Nordic Optical Telescope, Santa Cruz de La Palma, Spain), John Dickey (School of Mathematics & Physics, University of Tasmania, Australia) PKS B0208-512 is a blazar at a redshift of 1.0. VLBI observations show a strong core and a one sided jet. It was detected by the ROSAT all sky survey as an X-ray source and as a gamma-ray source by EGRET. Since the launch of Fermi, PKS B0208-512 has shown flaring behaviour in the gamma-ray band on at least three separate occasions. VLBI and radio light-curve monitoring observations of PKS B0208-512 is being conducted as part of the TANAMI program. Single-dish flux-density monitoring data obtained with the 30m Ceduna telescope date back to 2004 and show strong flaring behaviour in the radio band as well. Additional radio observations have been made using the Australia Telescope Compact Array and the source has been monitored in the optical band by the REM telescope. Archival X-ray and UV data have been obtained from the Swift satellite and its evolving parsec scale structure is being monitored with VLBI observations using the TANAMI array. We present the results of these multiwavelength observations and discuss the implications they have for the origin and nature of high energy emission from this blazar. In particular, we investigate the non simultaneous nature of the flaring at different frequencies. Modeling broadband spectra and variability of blazars Markus Böttcher (Astrophysical Institute, Department of Physics and Astronomy, Ohio University, Athens, OH 45701, USA) In this talk I will present a review of the current state-of-the-art of models for the broadband spectral energy distributions and variability of blazars. Both leptonic and hadronic models for blazar emission will be considered, with special attention to possible diagnostics to distinguish between those two classes of models. I will highlight areas of future progress to be made with continued Fermi as well as future CTA observations. A Diagnostic for Determining the Location of the GeV Emission in powerful blazars Amanda Dotson (University of Maryland Baltimore County), Markos Georganopoulos (University of Maryland Baltimore County,NASA/GSFC) , Demosthenes Kazanas (NASA/GSFC), Eric Perlman (Florida Institute of Technology) A central issue currently debated in the literature is how far from the black hole is the sl Fermi observed GeV emission of powerful blazars emitted. Here we present a clear diagnostic tool for testing whether the GeV emission site is located within the sub-pc broad emission line (BLR) region or further out in the few pc scale molecular torus environment. Within the BLR the scattering takes place at the onset of the Klein-Nishina regime, causing the electron cooling time to become practically energy independent and as a result, the variation of high-energy emission is expected to be achromatic. Contrarily, if the blazar is outside the BLR, the expected GeV variability is energy-dependent and with amplitude increasing with energy. We demonstrate this using time-dependent numerical simulations of blazar variability. The proposed work holds the promise of settling this important issue. 2 The ANTARES neutrino telescope Thomas Eberl (Erlangen Centre for Astroparticle Physics, Erwin-Rommel-Str. 1, D-91058 Erlangen) for the ANTARES collaboration The ANTARES deep-sea neutrino telescope currently is the largest neutrino detector in the North- ern Hemisphere. The instrument consists of a three-dimensional array of 885 photomultiplier tubes, arranged in 12 lines anchored at a depth of 2500m in the Mediterranean Sea, 40km offshore from Toulon (France). An additional instrumented line is used for environmental monitoring and for R&D towards acoustic neutrino detection. The photomultiplier tubes detect the Cherenkov radiation of charged secondary particles produced by high-energy neutrinos interacting in or around the detector. Charged-current interactions of muon neutrinos is the reaction channel of central interest. The tra- jectories of the resulting muons are reconstructed with high precision, revealing the direction of the incoming neutrinos. ANTARES is taking data with its full 12 line configuration since May 2008, and has been operated before in a 5 and 10 line setup for more than a year. The calibration, performance and long-term stability of the detector will be discussed. Studies have been underway to search for neutrino point sources in the ANTARES data since 2007. Results from these studies and the sensitivity of the telescope will be discussed. Before Fermi met Jansky Phil Edwards (CSIRO Astronomy & Space Science) Radio monitoring of gamma-ray emitting AGN in the EGRET era will be reviewed and key findings summarised, and efforts underway to continue, and improve upon, these studies in the Fermi era described. Blazar observations above 100 GeV with VERITAS Manel Errando (Barnard College/Columbia University) on behalf of the VERITAS collaboration The VERITAS array of 12-m atmospheric-Cherenkov telescopes in southern Arizona is one of the world’s most sensitive detectors of VHE (E>100 GeV) gamma rays. There are 50 extragalactic sources which are known to emit VHE photons, including blazars, radio galaxies, and starburst galaxies. Blazar observations are one of the VERITAS Collaboration’s Key Science Projects. More than 400 hours per year are devoted to this program and 100 blazars have already been observed with the array, in most cases with the deepest-ever VHE exposure. These observations have resulted in 21 detections, including 10 VHE discoveries, all of them with supporting multiwavelength observations. Recent highlights from VERITAS extragalactic observation program and the collaboration’s long-term blazar observation strategy will be presented. A Physical Model for the Revised Blazar Sequence Justin Finke (US Naval Research Laboratory) and Charles Dermer (US Naval Research Laboratory) The blazar sequence is reflected in a plot of the peak luminosity versus peak frequency of the syn- chrotron component of blazars.
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